The present application relates to a fusing method of a substrate layer, a manufacturing method of a microfluidic chip and a fusing apparatus of a substrate layer, and particularly to a fusing method of a substrate layer capable of performing superimposition of substrate layers by preventing deformation of a region formed on the substrate layer.
In recent years, by applying micro machining technologies in the semiconductor industry, a microfluidic chip having wells or flow paths for performing chemical and biological analyses on substrates made of silicon or glass has been developed (refer to Japanese Unexamined Patent Application Publication No. 2004-219199).
As an example, a microchip electrophoresis method of performing capillary electrophoresis using a microfluidic chip on which capillaries are formed by preparing a flow path (fine groove) on a plastic substrate layer and superimposing the substrate layer on an additional sheet of the substrate layer has been disclosed (refer to Japanese Unexamined Patent Application Publication No. 2004-219199 and Japanese Unexamined Patent Application Publication No. 2001-242138). The microchip electrophoresis method is used in analyses of chargeable trace substance such as nucleic acids, proteins, viruses, cells, amino acids, sugars, organic acids and ions.
In the microchip electrophoresis method, a microfluidic chip on which a sample introduction flow path and a sample separation flow path are formed so as to be at right angles to each other has been used (refer to FIG. 3 of Japanese Unexamined Patent Application Publication No. 2004-219199). In the microfluidic chip, an electrode is formed in the vicinity of an end point of the sample separation flow path using a printing method, a vapor deposition method, an etching method, a plating method or the like, and conductive path wiring for electrophoresis is performed (refer to Japanese Unexamined Patent Application Publication No. 2001-242138).